The present invention relates to vectorscope displays, and more particularly to a three-dimensional RGB component vector display in the form of a diamond to simplify the interpretation of the characteristics of respective color components, red (R), green (G) and blue (B).
The "Lightning" display, as incorporated into the WFM300 Waveform Monitor manufactured by Tektronix, Inc. of Wilsonville, Oregon, United States of America, is a method for measuring characteristics of a component color video signal having a luminance component and two color difference components, commonly referred to as Y, Pb and Pr. This display is described in U.S. Pat. No. 4,635,094 issued Jan. 6, 1987 to Tran Thong entitled "Method and Apparatus for Measurement of Component Video Signal Characteristics Using an Oscilloscope." This display is formed by inputting one color component to one axis of a display and the luminance component to the other, and then inputting the other color component to the one axis and an inverted luminance component to the other on alternating lines of the active video portion of the video signal. This display, when driven by RGB color components is difficult to interpret. The Lightning display is designed for Y, Pb, Pr, and an RGB input is matrixed to Y, Pb, Pr. This difficulty in interpretation occurs since Y is composed of a combination of all three RGB components and delay or gain errors of any one component always affects Y and, therefore, the entire display. If the RGB components are not matrixed to Y, Pb, Pr, then the Lightning display is very confusing since there is no longer a direct relationship between the RGB input and the Y, Pb, Pr display axes. Also with a Y, Pb, Pr display the gamut limit boundaries are not clearly defined.
What is desired is an RGB component vector display that is easy to interpret and defines clear gamut limit boundaries.